Computed tomography-guided percutaneous puncture injection of methylene blue mixed with autologous blood for preoperative localization of pulmonary nodules: analysis of 407 cases.

Background: Computed tomography (CT)-guided preoperative localization using methylene blue mixed with autologous blood is a commonly used technique for pulmonary nodules. However, its safety profile and risk factors for complications remain to be fully elucidated. This study aimed to evaluate the safety and complication risk of this technique and to explore the risk factors associated with the occurrence of complications. Methods: We conducted a retrospective analysis of 407 patients who underwent CT-guided percutaneous puncture of methylene blue mixed with autologous blood for localization of pulmonary nodules during thoracoscopic surgery from January 2021 to December 2025 at the Department of Thoracic Surgery, Central Hospital Affiliated to Shandong First Medical University. The patients were categorized into complication group and no complication group according to the presence or absence of complications. Complications were graded by severity according to the Clavien-Dindo classification. The clinical data of patients in the two groups were compared by univariable analysis and multivariable logistic regression analysis to explore the independent risk factors for patients to develop complications during localization, and to establish and validate the nomogram prediction model. Results: The localization success rate was 99.75% (406/407). For the single failed case, the nodule could still be located with the aid of preoperative imaging. The overall complication rate was 8.11% (33/407). The most common complication was pneumothorax, occurring in 7.37% (30/407) of cases, none of which required special intervention. Univariable analysis showed statistically significant differences in forced expiratory volume in 1 second as a percentage of the predicted value (FEV1% prediction), prothrombin time (PT), and nodule location between the two groups (P<0.05). Multivariable logistic regression analysis suggested that FEV1% prediction [odds ratio (OR) =0.118, 95% confidence interval (CI): 0.054-0.256, P<0.001], PT (OR =0.647, 95% CI: 0.421-0.994, P=0.047), and nodule location (OR =2.916, 95% CI: 1.188-7.156, P=0.019) were correlated with localization complications. The area under the receiver operating characteristic (ROC) curve for the nomogram prediction model was 0.855. After internal validation, the calibration curve of the model was highly compatible with the ideal curve with good goodness of fit (X Conclusions: CT-guided percutaneous puncture injection of methylene blue mixed with autologous blood is a safe and effective method for localizing pulmonary nodules. In addition, FEV1% prediction, PT and nodule location were independent risk factors for complications of this procedure.